Artificial foot piece



July 18, 1950 o. J. HowE ARTIFICIAL FOOT PIECE 2 Sheets-Sheet 1 Filed Jan. 9 1948 IN VENToR.

BY W 6 O. J. HOWE ARTIFICIAL FOOT PIECE July 1s, 195o 2 Sheets-Sheet 2 Filed Jan. 9, 1948 e d w ZL O Patented `Iuly 18, 1950 UNI-TED STATES PATENT OFFICE (Grarnted` under the act of March 3, 1883, asamended April 30, 1928; 370 0. G. 757) 6 Claims.

The invention described herein, if patented, may bemanufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to artificial feet and particularly tolarticial feet of a fragmentary nature such as are to be used by amputees who have lost only the front portion of a foot.

Itl is highly desirable in such cases that the articialportion of the foot shall iiex in the manner of .a normal foot so as to cause the shoe to break at the proper line and simulate the action of anormal foot and its shoe. It is also important that the stump receiving portion of the artificial foot be so constructed as to give the utmost comfort to the wearer by providing a snug fit and therebyy eliminating, or reducing to a minimum, any rubbing of the remaining portion of the natural' foot.

It is an object of the present invention, therefore, to provide an artificial foot piece adapted to. be secured in a. conventional shoe and having a bucket or pocket portion for snugly receiving and engaging the stump of `a natural foot, and designed in. a manner to eliminate painful rubbing.

It is another obj ect of' the invention to provide an artificial foot piece simulating the forward portion of a foot and having a flexible portion at the ball section thereof whereby in the act of walking the arti'cial foot piece will flex at' the break line of the shoe which incases iti and the stump ofthe wearers foot.

Other objects and advantages of the invention wil'lbe apparent from the following' description considered' in connection with the attachedrdrawings, i'n which,

Figure' 1 is `a perspective view of a shoewith the artificial foot piecemounted therein, a DortionI of the shoe being broken away for the purposeof showing the interior construction;

Figure 2 isa longitudinal sectional View through the footpiece perse with the stump indicated in dotted outline;

Figure 3' is a transverse sectionalview taken on line 3`-3 of Figure 1, with the shoe omitted;

Figure 4 is an inverted perspective view of the toe cap andv one of the parts to which it is immedately attached j Figure Bis alperspective View of a modified form` oflinsert;

Figurev 6 is avlongitudinal sectional View through the construction of Figure 5; and

Figure 7 Ais a cross sectional View taken onthe llnel'l--l'of Figure-6.

In the form of the invention illustrated in Figures 1 to 4 inclusive the numeral l indicates an insole for the shoe and to the rear portion of which is adhesively or otherwise secured a lining 2, preferably of leather. The rear portion ofthe insole and its lining 2 are molded to the shape of the heel portion of the wearers foot and the lin'- ing 2 is of suiiicient dimensions to provide an upwardly directed flange 3 to engage about the heel portion in the form of a pocket. The front wall of the pocket is formed of a strip of sponge rubber A the ends of which are beveled off and secured to the innerfaces of the side walls 3V by means of adhesive, as indicated by the numeral f1'. The pocket, which is to receive the stump of the wearers foot is made sufficiently long to provide a space for the cushion member 4 andadditional space to accommodate a sock.

A block of cork or other lightweight material, as indicated by the numeral 5, forms a substantial part of the foot piece and extends rearwardly from the ball portion of the insole to the sponge rubber block 4 to which it is adhesively secured. The lower portion of the cork block is provided with an extension 6 which is disposed between the insole l and the forward portion of the 1in-v ing 2 `and this cork piece 5-6 is adhesively sc cured to the upper face of the insole I and the lower face of the forward portion of the lining 2. Proper rigidity and durability are impartedv to the insole l, lining 2 and the cork block- 5 by coating and/or impregnating the exterior sure faces of these parts with shellacfor other suitable coating compound. It will also be noted that the cork strip 6 extends under the forward portion of the wearers foot and in effect constitutes a rigid extension thereof so as to` cause the foot piece to bend at its ball portion in the manner of a natural foot, thus providing an attendant breaking of the shoe at the break line in the conventional manner.

Adhesively secured to the forward face ofthe block 5 so as to span the ball portion of the insole I is a block of sponge rubber 'l the lower surface of which is adhesively secured to the insole Iv except for minor areas'at the ends thereof. The forward portion of the sponge rubber block` isy reduced slightly as indicated by numeral 8 to receive a hollow toe cap 9 of Celluloid or otherresilient material. This cap 9 is provided with an inturned flange I0 at its lower edgeand the ends of thisflange extend under the block l at the unsecured portion as indicated by the numeral Il. The verticalA dimensions of the rear portions of the toe cap 9` andthe forwardlreducec 3 portion of the rubber block 1 are such las to cause a relatively tight t as the cap is forced over the forward end of the rubber block as indicated in Figure 2.

In instances where the instep forms a part of the unamputated portion of the foot, it is desirable that means be incorporated on the `artificial foot piece for retaining the same on the wearers foot, and for this purpose an elastic web l2 is provided, a portion of which may be adhesively secured between the rear portion of the insole and the lining 2 as indicated by the numeral I3.

It will be understood, of course, that the upper surfaces of the toe cap 9, the rubber block 1, cork block and sponge rubber strip d are all rearwardly inclined upwardly to shape the artificial foot piece to that of a normal foot, and it should also be noted that the shoe, which is shown in Figure 1 and indicated by the numeral I4 is dimensioned to snugly receive the foot piece and the latter is permanently secured to the shoe by suitable adhesive or the like.

The modified form of the invention shown in Figures 5 to 7 inclusive is very much the same as that described above and consequently, the corresponding parts are indicated by the same reference numerals. The pocket in this modied form is dimensioned for use in those cases in which a substantially greater part of the foot has been removed than in the instances indicated in Figures 1 to 4 inclusive. `Due to the fact that there is relatively little of the sole of the foot in this case it is deemed desirable to add some resiliency to the foot piece and for this purpose a strip of sponge rubber 2li is adhesively or otherwise secured to the insole 2l which, of course is molded to t the heel portion of the wearers foot. This insole 2| is provided with an upwardly extending ange or wall 22 to provide a stump receiving pocket, and the forward end of the pocket is formed by a strip of sponge rubber 23 corresponding to the sponge rubber strip l of Figures 1 to 4 inclusive.

VThe cork block 24 which corresponds with the element 5 of Figure 2 may be adhesively secured to the insole 2| and the rubber strip 23 and is provided with an extension 25 passing below the sponge rubber strip 23 to which it is adhesively secured. This extension 25, in the same manner as the extension 6 of Figure 2 imparts the necessary rigidity to the mid-portion of the foot piece to cause the insole to iiex at the point of the rubberblock 1 in the same manner as mentioned in connection with the description of the foot piece illustrated in Figures 1 to 4 inclusive, with a con` sequent breaking of the shoe at the proper point. In this instance, also, the outer surface of the insole and the outer surface of the cork block 24 are coated and/or impregnated with shellac or other preferred compound for imparting rigidity and durability to these parts and the foot piece (as shown in Figures 5 to 7 inclusive) is permanently secured in a shoe by adhesive or otherwise,` as inthe previously described form of the invention.

In cases where this latter form of the invention will be used, an elastic strap such as the strap I2 would generally be without a function and, accordingly, no strap is shown in this modiiied form of the invention. However, the shoe to which the modied construction is attached will extend a substantial distance rearwardly of the rubber strip 23 and will thus serve in conjunction with the heel of the shoe to retain the shoe and its insert upon the -wearersfoot From the foregoing description and the accompanying drawings, it will be apparent to those skilled in the art that the present artiiicial foot piece is so designed as to provide a pocket to comfortably and snugly receive the stump of the wearers foot without undue rubbing of the parts; that the foot piece becomes in eiect a part of the natural foot; that the parts cooperate to cause the foot piece to flex at the ball portion thereof in simulation of a normal foot, and that the li-ability of slippage between the shoe, the foot piece, and the stump of the wearer is entirely eliminated.

In compliance with the patent statutes, I have described in detail what I now consider to be the preferred forms of the invention, but inasmuch as various changes may be made in structural features without deviating from the spirit of the invention, it is intended that all such details be included within the scope of the appended claims.

I claim: Y

1. An articial foot piece comprising an insole molded to iit the heel portion or stump 'of'a partly amputated foot, a cork portion simulating the shape of the front portion of a normal yfoot and extending from a line immediately behind the ball portion of the insole to a point adjacent the forward end of the stump, an extension at the bottom of the cork portion adapted to extend under the front portion of the stump a strip of sponge rubber secured to the rear edge of the cork portion and adapted to contact the front portion of the stump, and a block of sponge rub-f ber secured to the forward edge of the cork portion and extending across the ball portion of the insole. j

2. An artificial foot piecel comprising an insole molded to fit the heel portion or stump of a partly amputated foot, a cork portion simulating the shape of the front portion of a normal foot and extending from a line immediately behind the ball portion of the insole to a point adjacent the forward end of the stump, an extension at' the bottom of the cork portion adapted to extend under the front portion of the stump a strip' of sponge rubber secured to the rear edge ofthe cork portion and adapted to contact the front portion of the stump, and a hollow toe cap en-A gaging the forwardend of the insole and' extending to the last-mentioned of sponge rubber.

3. An artificial foot piece comprising lan insole molded to lt the heel portion or stump of a partly amputated foot, a cork portion simulatingv the shape of the front portion of a normal `foot and extending from a line immediately behind the ball portion of the insole to a point adjacent the forward end of the stump, an extension jat-the bottom of thel cork portion adapted to-extend under the front portion of the stump a stripo'f sponge rubber secured to the rear edge of 'the` cork portion and adapted to contact the front portion of the stump, and an elastic strap-having its ends secured to the sides of the insolel and adapted to engage over the instep'of the stump.

4. yAn artificial foot piece comprising an insole molded to t the heelportion or stump of a partly amputated foot, a cork portion simulating the shape of the front portion of a normal foot and extending from a line immediately behind'y the ball portion of the insole to a point adjacent the forward endrof the stump, anextension atpthe" bottom of the corkportion adapted to extend under the front portion of the stump astrip of sponge rubber'secured to the'rear-edge ofthe cork portion and adapted to contact the front portion of the stump, a block of sponge rubber secured to the forward edge of the cork portion and extending across the ball portion of the insole, a, toe cap of resilient material mounted on the toe portion of the insole, and a flange on the lower edge of the toe cap, the ends of said flange extending between the insole and the lower surface of the sponge rubber block.

5. An artioial foot piece comprising an insole molded to t the heel portion or stump of a 10 partly amputated foot, a cork portion simulating the shape of the front portion of a normal foot and extending from a line immediately behind the ball portion of the insole to a joint adjacent the front end of the stump, an extension at the bottom of the cork portion adapted to extend under the front portion of the stump, and a strip of sponge rubber secured to the rear edge of the cork portion.

6.- An artiiicial foot piece comprising an insole molded to t the heel portion or stump of a partly amputated foot, a cork portion simulating the shape and size of the front portion of a nor- REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Name Date Dumelin July 27, 1948 Number .GTI-IER REFERENCES Articial Limbs and Amputation Stumps by E. M. Little (1922), published by A. K. Lewis and Co., London, England. Pages 22'7, 228. Div. 55 of Patent Oce.

Copy in Certificate of Correction Patent No. 2,515,227 July 18, 1950 OLIVER J. HOWE It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 5, line 14, for the Word joint read point;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the ease in the Patent Office.

Signed and sealed this 10th day of October, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

